#ifndef MPU_THREADLOCK_H
#define MPU_THREADLOCK_H
#include "ptypes.h"
#ifdef STANDALONE
#undef USE_ITHREADS
#define MUTEX_INIT(x)
#define MUTEX_LOCK(x)
#define MUTEX_UNLOCK(x)
#define MUTEX_DESTROY(x)
#define COND_INIT(x)
#define COND_DESTROY(x)
#endif
#ifndef USE_ITHREADS
#define MUTEX_DECL(x)
#define READ_WRITE_LOCK_DECL(x)
#define WRITE_LOCK_START(x)
#define WRITE_LOCK_END(x)
#define READ_LOCK_START(x)
#define READ_LOCK_END(x)
#else
#define MUTEX_DECL(x) \
static perl_mutex x ## _mutex;
#define READ_WRITE_LOCK_DECL(x) \
static perl_mutex x ## _mutex; \
static perl_cond x ## _turn; \
static int x ## _reading; \
static int x ## _writing; \
static int x ## _writers;
#define WRITE_LOCK_START(x) \
do { \
MUTEX_LOCK(& x ## _mutex); \
x ## _writers++; \
while (x ## _reading || x ## _writing) \
COND_WAIT(& x ## _turn, & x ## _mutex); \
x ## _writing++; \
MUTEX_UNLOCK(& x ## _mutex); \
} while (0)
#define WRITE_LOCK_END(x) \
do { \
MUTEX_LOCK(& x ## _mutex); \
x ## _writing--; \
x ## _writers--; \
COND_BROADCAST(& x ## _turn); \
MUTEX_UNLOCK(& x ## _mutex); \
} while (0)
#define READ_LOCK_START(x) \
do { \
MUTEX_LOCK(& x ## _mutex); \
if (x ## _writers) \
COND_WAIT(& x ## _turn, & x ## _mutex); \
while (x ## _writing) \
COND_WAIT(& x ## _turn, & x ## _mutex); \
x ## _reading++; \
MUTEX_UNLOCK(& x ## _mutex); \
} while (0)
#define READ_LOCK_END(x) \
do { \
MUTEX_LOCK(& x ## _mutex); \
x ## _reading--; \
COND_BROADCAST(& x ## _turn); \
MUTEX_UNLOCK(& x ## _mutex); \
} while (0)
#endif
#endif